JP2017226719A - Urethane (meth) acrylate resin and laminate film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a urethane (meth) acrylate resin that imparts excellent performances such as excoriation resistance, curling resistance, flexibility, or impact resistance, to a cured coating; a curable composition containing the same and a cured product thereof; and a laminate film.SOLUTION: A urethane (meth) acrylate resin contains a polyisocyanate compound (A) represented by one of structural formulas (A-1) and (A-2) or a modified body thereof, and dipentaerythritol (meth) acrylate (B) as essential reaction materials. (l is an integer of 0 or more; m is 1 or 2; each Rindependently represents a C1-4 alkyl group, or a bonding point for bonding to a structural site inside parentheses in the formula via a methylene group with * mark; k is an integer of 0-2; n is an integer of 0-8).SELECTED DRAWING: None

Description

  The present invention relates to a urethane (meth) acrylate resin excellent in various properties such as scratch resistance, curl resistance, flexibility and impact resistance in a cured coating film, a curable composition containing the resin, a cured product thereof, and a laminate Related to film.

  Plastic films manufactured using polyethylene terephthalate resin (PET), acrylic resin, polycarbonate resin, acetylated cellulose resin, etc. are used in industrial applications such as polarizing plate protective films incorporated into flat panel displays and touch panel surface protective films. It is often used in. Since these plastic films are insufficient in performance, such as the surface is easily damaged by itself, the processability is low, and cracks and cracks are likely to occur, usually a coating layer made of active energy ray curable resin etc. is provided on the surface, It is used supplementing these performances.

  As a coating agent for reinforcing a plastic film, for example, a resin composition containing urethane acrylate obtained by reacting dipentaerythritol polyacrylate having a hydroxyl value of 80 to 120 mgKOH / g and hexamethylene diisocyanate is known. (See Patent Document 1). Although the resin composition described in Patent Document 1 has a high surface hardness in a cured product and excellent scratch resistance, curling is likely to occur, and the toughness and flexibility of the coating film are not sufficient. It was easy to produce a crack by.

International Publication No. 2010/146801

  Therefore, the problem to be solved by the present invention is a urethane (meth) acrylate resin excellent in various properties such as scratch resistance, curl resistance, flexibility, impact resistance, etc. in a cured coating film, and a curable composition containing the same. And a cured product thereof, and a laminated film.

  As a result of intensive studies to solve the above problems, the present inventor has, as essential components, a polyisocyanate compound having an isocyanate group on an aromatic ring or a cyclo ring or a modified product thereof, and dipentaerythritol (meth) acrylate. It has been found that a urethane (meth) acrylate resin obtained by the reaction solves the above problems, and has completed the present invention.

  That is, the present invention provides the following structural formula (A-1) or (A-2)

（式中、ｌは０又は１以上の整数であり、ｍは１又は２である。Ｒ^１はそれぞれ独立に炭素原子数１〜４のアルキル基、又は式中括弧内で表される構造部位と＊印が付されたメチレン基を介して連結する結合点の何れかであり、ｋは０、１又は２であり、ｎは０又は１〜８の整数である。）
の何れかで表されるポリイソシアネート化合物（Ａ）或いはその変性体と、ジペンタエリスリトール（メタ）アクリレート（Ｂ）とを必須の反応原料とするウレタン（メタ）アクリレート樹脂に関する。

(In the formula, l is 0 or an integer of 1 or more, and m is 1 or 2. R ¹ is each independently an alkyl group having 1 to 4 carbon atoms, or a structural moiety represented in parentheses in the formula. And k is 0, 1 or 2, and n is 0 or an integer of 1 to 8.)
Or a modified product thereof, and dipentaerythritol (meth) acrylate (B) as essential reaction raw materials.

  The present invention further relates to a curable composition containing the urethane (meth) acrylate resin and a photopolymerization initiator.

  The present invention further relates to a cured product obtained by curing the curable composition.

  The present invention further relates to a laminated film having a layer made of the cured product and another plastic film layer.

  According to the present invention, urethane (meth) acrylate resin excellent in various performances such as scratch resistance and curl resistance, flexibility, impact resistance in a cured coating film, a curable composition containing the same, and a cured product thereof, And a laminated film can be provided. The curable composition containing the urethane (meth) acrylate resin of the present invention can be suitably used as a reinforcing coating agent for various plastic films, and the laminated film obtained using the curable composition of the present invention is resistant to In addition to excellent scratch resistance and curl resistance, it has high flexibility and is resistant to cracking when bent or wound, and also has impact resistance that is resistant to cracking when there is a fallen object on the film.

  The urethane (meth) acrylate resin of the present invention has the following structural formula (A-1) or (A-2)

（式中、ｌは０又は１以上の整数であり、ｍは１又は２である。Ｒ^１はそれぞれ独立に炭素原子数１〜４のアルキル基、又は式中括弧内で表される構造部位と＊印が付されたメチレン基を介して連結する結合点の何れかであり、ｋは０、１又は２であり、ｎは０又は１〜８の整数である。）
の何れかで表されるポリイソシアネート化合物（Ａ）或いはその変性体と、ジペンタエリスリトール（メタ）アクリレート（Ｂ）とを必須の反応原料とする。

(In the formula, l is 0 or an integer of 1 or more, and m is 1 or 2. R ¹ is each independently an alkyl group having 1 to 4 carbon atoms, or a structural moiety represented in parentheses in the formula. And k is 0, 1 or 2, and n is 0 or an integer of 1 to 8.)
Or a modified product thereof and dipentaerythritol (meth) acrylate (B) as essential reaction raw materials.

  Regarding the polyisocyanate compound (A), l is 0 or an integer of 1 or more. Especially, since it becomes urethane (meth) acrylate resin excellent in the balance of the surface hardness in a cured coating film, a softness | flexibility, and impact resistance, it is preferable that l is 0 or 1. When l is 0, m in the formula is preferably 2. On the other hand, when l is 1, m in the formula is preferably 1. That is, the polyisocyanate compound (A) is preferably a diisocyanate compound having two isocyanate groups in one molecule, specifically, the following structural formulas (A-3) to (A-5):

（式中Ｒ^２はそれぞれ独立に炭素原子数１〜４のアルキル基であり、ｋは０、１又は２であり、ｎは０又は１〜８の整数である。）
の何れかで表されるポリイシアネート化合物であることが特に好ましい。

(In the formula, each R ² is independently an alkyl group having 1 to 4 carbon atoms, k is 0, 1 or 2, and n is 0 or an integer of 1 to 8).
It is particularly preferable that the polyisocyanate compound represented by any of the above.

  The modified product of the polyisocyanate compound (A) is a modified polyisocyanate compound using the polyisocyanate compound (A) as a raw material, and is obtained, for example, by converting the polyisocyanate compound (A) to isocyanurate. Isocyanurate-modified product, adduct-modified product obtained by reacting the polyisocyanate compound (A) with a polyol compound, biuret-modified product of the polyisocyanate compound (A), and allophanate-modified product of the polyisocyanate compound (A) Etc. In the present invention, as the polyisocyanate compound (A) or a modified product thereof, one type may be used alone, or two or more types may be used in combination.

  The dipentaerythritol (meth) acrylate (B) is obtained by converting a part of the hydroxyl group of dipentaerythritol into (meth) acrylate and having a hydroxyl group capable of reacting with the polyisocyanate compound (A). A single compound or a mixture of a plurality of compounds may be used. That is, in the former case, as dipentaerythritol (meth) acrylate (B), dipentaerythritol mono (meth) acrylate, dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol Tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate are each used alone. In the latter case, dipentaerythritol mono (meth) acrylate, dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate 1 type or multiple types of this, and may contain dipentaerythritol hexa (meth) acrylate as needed.

  Above all, the dipentaerythritol (meth) acrylate (B) is a dipentaerythritol tetra (meth) acrylate because it becomes a urethane (meth) acrylate resin having a good balance of surface hardness, flexibility and impact resistance in a cured coating film. (B1) is preferably contained as an essential component, more preferably dipentaerythritol tetra (meth) acrylate (b1) and dipentaerythritol penta (meth) acrylate (b2), and dipentaerythritol tetra ( It is particularly preferable to contain (meth) acrylate (b1), dipentaerythritol penta (meth) acrylate (b2) and dipentaerythritol hexa (meth) acrylate (b3).

  When the dipentaerythritol (meth) acrylate (B) contains dipentaerythritol tetra (meth) acrylate (b1) as an essential component, the content is preferably in the range of 1 to 30%, A range of 25% is more preferable, and a range of 3 to 20% is particularly preferable.

In the present invention, the content of each component in the dipentaerythritol (meth) acrylate (B) and the ratio of the content of each component are calculated from the area ratio of the liquid chromatography chart measured under the following conditions. Value.
[Measurement condition]
Equipment: “LCMS-2010EV” manufactured by Shimadzu Corporation
Data processing: “LCMS Solution” manufactured by Shimadzu Corporation
Column: “ODS-100V” manufactured by Tosoh Corporation (2.0 mm ID × 150 mm, 3 μm) 40 ° C.
Eluent: Water / acetonitrile, 0.4 mL / min Detector: PDA, MS
Sample preparation: 1. Dissolve 50 mg of material in 10 ml of acetonitrile (for LC)
2. Vortex for 30 seconds
3. Leave for 30 minutes
4. Calculation of the area ratio as a measurement sample by passing through a 0.2 μm filtration filter: calculated at a UV wavelength of 210 nm

  When the dipentaerythritol (meth) acrylate (B) contains dipentaerythritol tetra (meth) acrylate (b1) and dipentaerythritol penta (meth) acrylate (b2), the ratio of the contents of both [(b1) / (B2)] is preferably in the range of 1/99 to 50/50, and more preferably in the range of 5/95 to 30/70.

  When the dipentaerythritol (meth) acrylate (B) contains dipentaerythritol hexa (meth) acrylate (b3), the content is preferably in the range of 1 to 60%, and in the range of 5 to 50%. It is more preferable that

  Moreover, since the hydroxyl value of the dipentaerythritol (meth) acrylate (B) is a urethane (meth) acrylate resin having an excellent balance of surface hardness, flexibility, and impact resistance in the cured coating film, 50 to 140 mgKOH / It is preferable that it is the range of g, and it is more preferable that it is the range of 65-130 mgKOH / g. In the present invention, the hydroxyl value of dipentaerythritol (meth) acrylate (B) is calculated from an actual value measured according to JIS K 0070 or a composition ratio of each component calculated from an area ratio of a liquid chromatography chart. It is a calculated value.

  Although the manufacturing method of the said dipentaerythritol (meth) acrylate (B) is not specifically limited, For example, the method of making esterification reaction of dipentaerythritol and acrylic acid is mentioned. When producing by this method, as a by-product other than the dipentaerythritol (meth) acrylate (B), a high molecular weight component (b ′) such as an addition reaction product of dipentaerythritol (meth) acrylate (B), etc. May generate. The high molecular weight component (b ') may be purified and removed, or may be used as a raw material for the urethane (meth) acrylate resin as a dipentaerythritol (meth) acrylate (B) crude product containing it. At this time, it is preferable that content of the said high molecular weight component (b ') in a dipentaerythritol (meth) acrylate (B) crude product is the range of 1-20 mass%.

  Further, since the hydroxyl value of the dipentaerythritol (meth) acrylate (B) crude product is a urethane (meth) acrylate resin having an excellent balance of surface hardness, flexibility and impact resistance in the cured coating film, 60 It is preferable to be in the range of ˜150 mg KOH / g. In the present invention, the hydroxyl value of dipentaerythritol (meth) acrylate (B) is a measured value measured according to JIS K 0070.

  The urethane (meth) acrylate resin uses the polyisocyanate compound (A) and dipentaerythritol (meth) acrylate (B) as essential reaction raw materials, but compounds other than these may be used as reaction raw materials. Specifically, in addition to the polyisocyanate compound (A) and dipentaerythritol (meth) acrylate (B), other polyisocyanate compounds (C), other monohydroxy (meth) acrylate compounds (D), What is obtained by making other polyol compounds (E) etc. react is mentioned.

  Examples of the other polyisocyanate compound (C) include aliphatic diisocyanate compounds such as butane diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and 2,4,4-trimethylhexamethylene diisocyanate; isophorone diisocyanate And alicyclic diisocyanate compounds such as these isocyanurate-modified products, biuret-modified products, and allophanate-modified products. These may be used alone or in combination of two or more.

  When using the said other polyisocyanate compound (C), since the effect of this invention is fully exhibited, it is with respect to the total mass of the said polyisocyanate compound (A) and the said other polyisocyanate compound (C). The proportion of the polyisocyanate compound (A) is preferably 30% by mass or more, and more preferably 50% by mass or more.

  Examples of the other monohydroxy (meth) acrylate compound (D) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and glycerin di (meth) acrylate. Aliphatic (meth) acrylate compounds such as trimethylolpropane di (meth) acrylate and pentaerythritol tri (meth) acrylate; 4-hydroxyphenyl acrylate, β-hydroxyphenethyl acrylate, 4-hydroxyphenethyl acrylate, acrylic acid Aromatic ring-containing (meth) acrylate compounds such as 1-phenyl-2-hydroxyethyl, 3-hydroxy-4-acetylphenyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate; Polyether modification (meta) obtained by ring-opening polymerization of a relate compound with various cyclic ether compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether. ) Acrylate compounds; lactone-modified (meth) acrylate compounds obtained by polycondensation of the (meth) acrylate compounds and lactone compounds such as ε-caprolactone. These may be used alone or in combination of two or more. Especially, since it becomes urethane (meth) acrylate resin excellent in the softness | flexibility and impact resistance in hardened | cured material, an aliphatic (meth) acrylate compound or its polyether modified body and a lactone modified body are preferable.

  Examples of the other polyol compound (E) include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, and 3-methyl-1,3-butane. Diol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, glycerol, glycerol mono (meth) acrylate, trimethylolethane, trimethylolmethane mono (meth) acrylate, trimethylolpropane, trimethylolpropane mono Polyol monomers such as (meth) acrylate, pentaerythritol mono (meth) acrylate, pentaerythritol di (meth) acrylate; the polyol monomer and succinic acid, adipic acid, azelaic acid, sebacine By co-condensation with dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, 1,4-cyclohexanedicarboxylic acid Polyester polyol obtained; lactone-type polyester polyol obtained by polycondensation reaction of the polyol monomer with various lactones such as ε-caprolactone, δ-valerolactone, 3-methyl-δ-valerolactone; Examples include polyether polyols obtained by ring-opening polymerization with cyclic ether compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, and propyl glycidyl ether. These polyol compounds may be used alone or in combination of two or more.

  The method for producing the urethane (meth) acrylate resin of the present invention includes, for example, the polyisocyanate compound (A) and dipentaerythritol (meth) acrylate (B), an isocyanate group that the polyisocyanate compound (A) has, The dipentaerythritol (meth) acrylate (B) has a molar ratio [(NCO) / (OH)] to the hydroxyl group of the dipentaerythritol (meth) acrylate (B) in the range of 1 / 0.95 to 1 / 1.05. Examples thereof include a method performed using a known and usual urethanization catalyst within a temperature range of 120 ° C., if necessary.

  In addition to the polyisocyanate compound (A) and the dipentaerythritol (meth) acrylate (B), the other polyisocyanate compound (C), the other monohydroxy (meth) acrylate compound (D), When other polyol compound (E) is reacted, a method of reacting these three components at once may be used, or an intermediate is obtained by first reacting a polyisocyanate component and a polyol component, and then a monoalcohol component is reacted. A method of reacting or a method of reacting the polyisocyanate component and the monoalcohol component first to obtain an intermediate and then reacting the polyol component may be used. The reaction ratio of each component is such that the total molar ratio [(NCO) / (OH)] of the isocyanate group of the polyisocyanate component and the hydroxyl group of the alcohol component is 1 / 0.95 to 1 / 1.05. It is preferable that the ratio is

  The (meth) acryloyl group equivalent of the urethane (meth) acrylate resin of the present invention is in the range of 100 to 500 g / eq because it becomes a urethane (meth) acrylate resin having excellent curability and high surface hardness in the cured coating film. It is preferable. In the present invention, the (meth) acryloyl group equivalent of the urethane (meth) acrylate resin is a value calculated as a theoretical value from the reaction raw materials.

  Moreover, since the weight average molecular weight (Mw) of the said urethane (meth) acrylate resin becomes a urethane (meth) acrylate resin excellent in the balance of each performance in hardened | cured material, it is the range of 2,000-60,000. Is preferred.

In the present invention, the weight average molecular weight (Mw) is a value measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device: HLC-8220GPC manufactured by Tosoh Corporation
Column: TSK-GUARDCOLUMN SuperHZ-L manufactured by Tosoh Corporation
+ Tosoh Corporation TSK-GEL SuperHZM-M x 4
Detector: RI (differential refractometer)
Data processing: Multi-station GPC-8020 model II manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Solvent tetrahydrofuran
Flow rate: 0.35 ml / min Standard: Monodispersed polystyrene Sample: Filtered 0.2% by mass tetrahydrofuran solution in terms of resin solids with a microfilter (100 μl)

  The curable composition of this invention contains the said urethane (meth) acrylate resin and a photoinitiator. Examples of the photopolymerization initiator include benzophenone, 3,3′-dimethyl-4-methoxybenzophenone, 4,4′-bisdimethylaminobenzophenone, 4,4′-bisdiethylaminobenzophenone, and 4,4′-dichloro. Various benzophenones such as benzophenone, Michler's ketone, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone;

Xanthones, thioxanthones such as xanthone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone; various acyloin ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether;

  Α-diketones such as benzyl and diacetyl; sulfides such as tetramethylthiuram disulfide and p-tolyl disulfide; various benzoic acids such as 4-dimethylaminobenzoic acid and ethyl 4-dimethylaminobenzoate;

  3,3′-carbonyl-bis (7-diethylamino) coumarin, 1-hydroxycyclohexyl phenyl ketone, 2,2′-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1- [4 -(Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-hydroxy-2-methyl-1- Phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 1- [4- (2-hydroxyethoxy) phenyl] -2- Hydroxy-2-methyl-1-propan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2- Tylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 4-benzoyl-4'-methyldimethylsulfide, 2,2'-diethoxyacetophenone, benzyldimethyl Ketal, benzyl-β-methoxyethyl acetal, methyl o-benzoylbenzoate, bis (4-dimethylaminophenyl) ketone, p-dimethylaminoacetophenone, α, α-dichloro-4-phenoxyacetophenone, pentyl-4- Dimethylaminobenzoate, 2- (o-chlorophenyl) -4,5-diphenylimidazolyl dimer, 2,4-bis-trichloromethyl-6- [di- (ethoxycarbonylmethyl) amino] phenyl-S-triazine, 2 , 4-Bis-trichloromethyl-6- (4-ethoxy Phenyl-S-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4-ethoxy) phenyl-S-triazineanthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, etc. Is mentioned. These may be used alone or in combination of two or more.

  Among the photopolymerization initiators, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy- 2-methyl-1-propan-1-one, thioxanthone and thioxanthone derivatives, 2,2′-dimethoxy-1,2-diphenylethane-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2 , 4,6-trimethylbenzoyl) phenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholino One or more mixed systems selected from the group of phenyl) -butan-1-one By are more active against a broad range of wavelengths of light is preferred because the high curability curable composition.

  Commercially available products of the photopolymerization initiator include, for example, “Irgacure-184”, “Irgacure-149”, “Irgacure-261”, “Irgacure-369”, “Irgacure-500”, “Irgacure-” manufactured by Ciba Specialty Chemicals. "Irgacure-754", "Irgacure-784", "Irgacure-819", "Irgacure-907", "Irgacure-1116", "Irgacure-1664", "Irgacure-1700", "Irgacure-1800" "Irgacure-1850", "Irgacure-2959", "Irgacure-4043", "Darocur-1173"; "Lucirin TPO" manufactured by BASF; "Kayacure-DETX", "Kayacure-MBP" manufactured by Nippon Kayaku ”,“ Kayaki “A-DMBI”, “Kayacure-EPA”, “Kayacure-OA”; “Bicure-10”, “Bicure-55” manufactured by Stowa Chemical; “Trigonal P1” manufactured by Akzo; “Deep” manufactured by Apjon; “QuantaCure-PDO”, “QuantaCure-ITX”, “QuantaCure-EPD”, etc. manufactured by Ward Brenkinsop.

  The addition amount of the photopolymerization initiator is an amount that can sufficiently exhibit the function as a photopolymerization initiator, and is preferably in a range in which precipitation of crystals and deterioration of physical properties of the coating film do not occur. It is preferable to use it in the range of 0.05-20 mass parts with respect to 100 mass parts of curable compositions, and it is especially preferable to use in the range of 0.1-10 mass parts.

  The curable composition of the present invention may contain various photosensitizers in combination with the photopolymerization initiator. Examples of the photosensitizer include amines, ureas, sulfur-containing compounds, phosphorus-containing compounds, chlorine-containing compounds, nitriles, and other nitrogen-containing compounds.

  The curable composition of the present invention further includes other photocurable compounds other than the urethane (meth) acrylate resin of the present invention, organic solvents, ultraviolet absorbers, antioxidants, silicon-based additives, and fluorine-based additives. Agents, silane coupling agents, organic beads, inorganic fine particles, inorganic fillers, rheology control agents, defoaming agents, antifogging agents, coloring agents, and the like may be contained.

  Examples of the other photocurable compounds include various (meth) acrylate monomers, other urethane (meth) acrylate resins other than the urethane (meth) acrylate resin of the present invention, and epoxy (meth) acrylate resins. Is mentioned.

  Examples of the (meth) acrylate monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) ) Acrylate, t-butyl (meth) acrylate, glycidyl (meth) acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isobornyl (meth) Acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate Relate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl carbitol (meth) acrylate, phosphoric acid (meth) acrylate, ethylene oxide modified phosphoric acid (meth) acrylate, phenoxy (meth) acrylate , Ethylene oxide modified phenoxy (meth) acrylate, propylene oxide modified phenoxy (meth) acrylate, nonylphenol (meth) acrylate, ethylene oxide modified nonylphenol (meth) acrylate, propylene oxide modified nonylphenol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, Methoxypolyethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, 2- (Meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl hydrogen phthalate, 2- (meth) acryloyloxypropyl hydrogen phthalate, 2- ( (Meth) acryloyloxypropyl hexahydrohydrogen phthalate, 2- (meth) acryloyloxypropyl tetrahydrophthalate, dimethylaminoethyl (meth) acrylate, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl ( (Meth) acrylate, octafluoropropyl (meth) acrylate, octafluoropropyl (meth) acrylate, adamantyl Mono (meth) acrylates such as mono (meth) acrylate;

  Butanediol di (meth) acrylate, hexanediol di (meth) acrylate, ethoxylated hexanediol di (meth) acrylate, propoxylated hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate , Polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethoxylated neopentyl glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, trimethylol Di (meth) acrylates such as propanedi (meth) acrylate and pentaerythritol di (meth) acrylate;

  Trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, pentaerythritol tri Tri (meth) acrylates such as (meth) acrylate and dipentaerythritol tri (meth) acrylate;

  Pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, ditrimethylolpropane penta (meth) acrylate, dipentaerythritol hexa (meta) 4) or more functional (meth) acrylates such as acrylate, ditrimethylolpropane hexa (meth) acrylate;

  Examples thereof include (meth) acrylates in which some or all of the various polyfunctional (meth) acrylates are modified with a polyoxyalkylene chain or a polyester chain.

  The other urethane (meth) acrylate resin may be, for example, a urethane (meth) acrylate resin using a compound other than the polyisocyanate compound (A) as a polyisocyanate compound, or dipentaerythritol (meta) as a hydroxy (meth) acrylate compound. ) Urethane (meth) acrylate resin using a compound other than acrylate (B).

  Examples of the epoxy (meth) acrylate resin include compounds obtained by (meth) acrylate formation by reacting various epoxy resins such as bisphenol type epoxy resin and novolac type epoxy resin with (meth) acrylic acid or a derivative thereof.

  These other photocurable compounds may be used alone or in combination of two or more. Especially, since it becomes a composition excellent in sclerosis | hardenability, it is preferable to use various (meth) acrylate monomers. When using these other photocurable compounds, the urethane (meth) acrylate resin of the present invention is 5 parts by mass in a total of 100 parts by mass of the urethane (meth) acrylate resin of the present invention and the other photocurable compounds. It is preferable to use it in the ratio which becomes above, and it is especially preferable to use it in the ratio which becomes 20 mass parts or more.

  Examples of the organic solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone (ketone solvents such as tetrahydrofuran; cyclic ether solvents such as tetrahydrofuran and dioxolane; esters such as methyl acetate, ethyl acetate, and butyl acetate; aromatic solvents such as toluene and xylene; Alcohol solvents such as carbitol, cellosolve, methanol, isopropanol, butanol, propylene glycol monomethyl ether; glycol ether solvents such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether These may be used alone or in combination of two or more.

  These organic solvents are used mainly for the purpose of adjusting the viscosity of the curable composition, but it is usually preferable to adjust so that the nonvolatile content is in the range of 10 to 80% by mass.

  Examples of the ultraviolet absorber include 2- [4-{(2-hydroxy-3-dodecyloxypropyl) oxy} -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1, 3,5-triazine, 2- [4-{(2-hydroxy-3-tridecyloxypropyl) oxy} -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3 Triazine derivatives such as 2,5-triazine, 2- (2'-xanthenecarboxy-5'-methylphenyl) benzotriazole, 2- (2'-o-nitrobenzyloxy-5'-methylphenyl) benzotriazole, 2- Xanthenecarboxy-4-dodecyloxybenzophenone, 2-o-nitrobenzyloxy-4-dodecyloxybenzophenone, and the like. These may be used alone or in combination of two or more.

  Examples of the antioxidant include hindered phenol-based antioxidants, hindered amine-based antioxidants, organic sulfur-based antioxidants, and phosphate ester-based antioxidants. These may be used alone or in combination of two or more.

  Examples of the silicon-based additive include dimethylpolysiloxane, methylphenylpolysiloxane, cyclic dimethylpolysiloxane, methylhydrogenpolysiloxane, polyether-modified dimethylpolysiloxane copolymer, polyester-modified dimethylpolysiloxane copolymer, and fluorine-modified dimethyl. Examples include polyorganosiloxanes having alkyl groups and phenyl groups, such as polysiloxane copolymers and amino-modified dimethylpolysiloxane copolymers, polydimethylsiloxanes having polyether-modified acrylic groups, and polydimethylsiloxanes having polyester-modified acrylic groups. It is done. These may be used alone or in combination of two or more.

  Examples of the fluorine-based additive include DIC Corporation “Megafac” series. These may be used alone or in combination of two or more.

  Examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3- Glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyl Diethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) ) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl- N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, special Aminosilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropylate Ethoxysilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, trichlorovinylsilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, etc., vinyl -Based silane coupling agents;

  Diethoxy (glycidyloxypropyl) methylsilane, 2- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-bridoxypropyl Epoxy-based silane coupling agents such as triethoxysilane;

  styrenic silane coupling agents such as p-styryltrimethoxysilane;

  3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, etc. (meth) Acryloxy silane coupling agent;

  N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) 3-aminopropyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropyltriethoxysilane, 3-aminopropyltri Amino-based silane couplings such as methoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane Agent;

  Ureido-based silane coupling agents such as 3-ureidopropyltriethoxysilane;

  Chloropropyl-based silane coupling agents such as 3-chloropropyltrimethoxysilane;

  Mercaptopropyl silane coupling agents, such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethinesilane;

  Sulfide-based silane coupling agents such as bis (triethoxysilylpropyl) tetrasulfide;

  Examples thereof include isocyanate-based silane coupling agents such as 3-isocyanatopropyltriethoxysilane. These may be used alone or in combination of two or more.

  Examples of the organic beads include polymethyl methacrylate beads, polycarbonate beads, polystyrene beads, polyacryl styrene beads, silicone beads, glass beads, acrylic beads, benzoguanamine resin beads, melamine resin beads, polyolefin resin beads, Examples thereof include polyester resin beads, polyamide resin beads, polyimide resin beads, polyfluorinated ethylene resin beads, and polyethylene resin beads. These may be used alone or in combination of two or more. The average particle diameter of these organic beads is preferably in the range of 1 to 10 μm.

  Examples of the inorganic fine particles include fine particles of silica, alumina, zirconia, titania, barium titanate, antimony trioxide, and the like. These may be used alone or in combination of two or more. The average particle diameter of these inorganic fine particles is preferably in the range of 95 to 250 nm, and more preferably in the range of 100 to 180 nm. Further, when these inorganic fine particles are contained, a dispersion aid may be further used. Examples of the dispersion aid include phosphate esters such as isopropyl acid phosphate, triisodecyl phosphite, and ethylene oxide-modified phosphate dimethacrylate. Compounds and the like. These may be used alone or in combination of two or more.

  Examples of commercially available dispersion aids include “Kayamar PM-21” and “Kayamer PM-2” manufactured by Nippon Kayaku Co., Ltd., “Light Ester P-2M” manufactured by Kyoeisha Chemical Co., Ltd., and the like.

  The curable composition of the present invention can be used for coating applications, and the coating is applied as a coating layer that protects the surface of the substrate by coating on various substrates and irradiating and curing with active energy rays. be able to. In this case, the curable composition of the present invention may be directly applied to the surface-protecting member, or one applied on a plastic film may be used as the protective film. Or what applied the curable composition of this invention on the plastic film, and formed the coating film may be used as optical films, such as an antireflection film, a diffusion film, and a prism sheet. The cured coating film of the curable composition of the present invention is characterized by high surface hardness and excellent flexibility and impact resistance. Therefore, it is applied to various types of plastic films with a film thickness according to the application, and a protective film. It can be used as a use or a film-like molded product.

  The plastic film is, for example, a plastic film made of polycarbonate, polymethyl methacrylate, polystyrene, polyester, polyolefin, cycloolefin, epoxy resin, melamine resin, triacetyl cellulose resin, ABS resin, AS resin, norbornene resin, polyimide resin, or the like. And plastic sheets.

  Among the plastic films, the triacetyl cellulose film is a film that is particularly suitably used for the polarizing plate application of a liquid crystal display. However, since the thickness is generally as thin as 40 to 100 μm, the surface even when a hard coat layer is installed. It is difficult to make the hardness sufficiently high, and there is a feature that it is easily curled. The coating film comprising the curable composition of the present invention has a high surface hardness even when a triacetyl cellulose film is used as a base material, and has an effect of excellent curling resistance, flexibility, transparency and impact resistance. Can be suitably used. When using the triacetyl cellulose film as a substrate, the coating amount when applying the curable composition of the present invention is such that the film thickness after drying is in the range of 1 to 20 μm, preferably in the range of 2 to 10 μm. It is preferable to apply to. Examples of the coating method at that time include bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, offset printing, flexographic printing, and screen printing.

  Among the plastic films, examples of the polyester film include polyethylene terephthalate, and the thickness thereof is generally about 20 to 300 μm. Although it is a cheap and easy to process film, it is a film used for various applications such as a touch panel display. However, it is very soft and has a feature that it is difficult to sufficiently increase the surface hardness even when a hard coat layer is provided. When using the polyethylene film as a substrate, the coating amount when applying the curable composition of the present invention is such that the film thickness after drying ranges from 1 to 100 μm, preferably from 1 to 20 μm, in accordance with the application. It is preferable to apply in such a range. In general, a cured coating film having a thickness exceeding 20 μm tends to curl greatly as compared with a case where the film thickness is small. However, the curable composition of the present invention also has a feature of excellent curling resistance, and therefore has a characteristic of 30 μm. Curling hardly occurs even when the film is applied with a relatively high film thickness exceeding 50, and can be suitably used. Examples of the coating method at that time include bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, offset printing, flexographic printing, and screen printing.

  Among the plastic films, the polymethyl methacrylate film is generally relatively thick and durable with a thickness of about 50 to 2,000 μm, so it is suitable for applications that require a particularly high surface hardness, such as applications for the front plate of liquid crystal displays. It is the film used for. When the polymethyl methacrylate film is used as a base material, the coating amount when applying the curable composition of the present invention is in the range of 1 to 100 μm, preferably 1 to 100 μm after drying according to the application. It is preferable to apply in a range of 20 μm. Examples of the coating method at that time include bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, offset printing, flexographic printing, and screen printing.

  Of the plastic films, cycloolefin polymer films are generally weak against lateral forces such as tearing, and are known to have poor folding resistance, but in recent years from the viewpoint of transparency and heat resistance. The area of use is expanding. The cured coating film obtained from the curable composition of the present invention can effectively increase its flexibility and impact resistance even in such a fragile film. From the viewpoint of suitably exhibiting such an effect, the thickness of the cured coating film is preferably adjusted in the range of 1 to 10 μm. Examples of the coating method at that time include bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, offset printing, flexographic printing, and screen printing.

  Examples of the active energy rays irradiated when the curable composition of the present invention is cured to form a coating film include ultraviolet rays and electron beams. In the case of curing with ultraviolet rays, an ultraviolet irradiation device having a xenon lamp, a high-pressure mercury lamp, a metal halide lamp, an LED or the like as a light source is used, and the amount of light, the arrangement of the light source, and the like are adjusted as necessary. When using a high-pressure mercury lamp, it is preferable to cure at a conveyance speed of 5 to 50 m / min for one lamp having a light quantity that is usually in the range of 80 to 160 W / cm. On the other hand, in the case of curing with an electron beam, it is preferably cured with an electron beam accelerator having an accelerating voltage that is usually in the range of 10 to 300 kV at a conveyance speed of 5 to 50 m / min.

  Moreover, the base material to which the curable composition of the present invention is applied is suitably used not only as a plastic film but also as a surface coating agent for various plastic molded articles, for example, cellular phones, electric appliances, automobile bumpers and the like. be able to. In this case, examples of the method for forming the coating film include a coating method, a transfer method, and a sheet bonding method.

  The coating method is a method in which the paint is spray-coated or coated as a top coat on a molded product using a printing device such as a curtain coater, roll coater, gravure coater, etc., and then cured by irradiation with active energy rays. is there.

  The laminated film of the present invention has a cured coating film or the like of the curable composition of the present invention and a plastic film layer, and additionally has functional film layers such as an antireflection film, a diffusion film, and a polarizing film. You may do it. These various layer configurations may be formed by a method in which a resin raw material is directly applied and dried or cured, or may be formed by a method of bonding through an adhesive layer.

  Hereinafter, the present invention will be described more specifically with reference to specific production examples and examples, but the present invention is not limited to these examples. Unless otherwise indicated, all parts and percentages in the examples are based on mass.

  In this example, the weight average molecular weight (Mw) is a value measured under the following conditions using a gel permeation chromatograph (GPC).

Measuring device: HLC-8220 manufactured by Tosoh Corporation
Column: Guard column H _XL- H manufactured by Tosoh Corporation
+ Tosoh Corporation TSKgel G5000HXL
+ Tosoh Corporation TSKgel G4000HXL
+ Tosoh Corporation TSKgel G3000HXL
+ Tosoh Corporation TSKgel G2000HXL
Detector: RI (differential refractometer)
Data processing: Tosoh Corporation SC-8010
Measurement conditions: Column temperature 40 ° C
Solvent tetrahydrofuran
Flow rate: 1.0 ml / min Standard: Polystyrene sample: 0.4 mass% tetrahydrofuran solution filtered in terms of resin solids with a microfilter (100 μl)

In this example, the liquid chromatography chart was measured under the following conditions.
[Measurement condition]
Equipment: “LCMS-2010EV” manufactured by Shimadzu Corporation
Data processing: “LCMS Solution” manufactured by Shimadzu Corporation
Column: “ODS-100V” manufactured by Tosoh Corporation (2.0 mm ID × 150 mm, 3 μm) 40 ° C.
Eluent: Water / acetonitrile, 0.4 mL / min Detector: PDA, MS
Sample preparation: 1. Dissolve 50 mg of material in 10 ml of acetonitrile (for LC)
2. Vortex for 30 seconds
3. Leave for 30 minutes
4. Calculation of the area ratio for passing through a 0.2 μm filtration filter to make a measurement sample: calculation at a UV wavelength of 210 nm

Production Example 1 Production of Dipentaerythritol Polyacrylate (B1) Crude Product In a flask equipped with a thermometer, a stirrer, and a condenser, 300 g of acrylic acid, 180 g of dipentaerythritol, 15 g of sulfuric acid, 1.5 g of cupric chloride, 300 g of toluene was charged. The temperature was raised to 105 ° C. with stirring, and the reaction was carried out at the same temperature for 12 hours while refluxing the system. The produced water was 68.5 g. To the reaction mixture, 425 g of toluene was added and washed with 200 g of distilled water. Further, 20% aqueous sodium hydroxide solution was added to neutralize the reaction mixture, and the mixture was washed with 100 g of distilled water. After adding 500 ppm of hydroquinone monomethyl ether to the resin solid content, toluene was distilled off to obtain dipentaerythritol poly (meth) acrylate (B1). The hydroxyl value of the dipentaerythritol polyacrylate (B1) crude product is 88 mgKOH / g, the content of dipentaerythritol tetraacrylate (b1) calculated from the area ratio of the liquid chromatography chart is 7.2%, dipentaerythritol The content of pentaacrylate (b2) was 48.3%, the content of dipentaerythritol hexaacrylate (b3) was 30.7%, and the content of the high molecular weight component (b ′) was 13.8%. The hydroxyl value of dipentaerythritol polyacrylate (B1) calculated from the content ratio of each component is 79.9 mgKOH / g.

Production Examples 2 to 4 Production of Dipentaerythritol Polyacrylates (B2) to (B4) Crude Products Dipentapentite was prepared in the same manner as in Production Example 1 except that the amount of acrylic acid charged and the reaction time were changed as shown in Table 1. Crude products of erythritol polyacrylates (B2) to (B4) were obtained. Dipentaerythritol polyacrylate (B2) to (B4) The hydroxyl value of the crude product, the content of each component calculated from the area ratio of the liquid chromatography chart, the dipentaerythritol poly calculated from the content ratio of each component Table 1 shows the hydroxyl values of acrylates (B2) to (B4).

Example 1 Production of Urethane (Meth) acrylate Resin (1) Composition In a flask equipped with a thermometer, a stirrer, and a condenser, 638 g of the dipentaerythritol polyacrylate (B1) crude product obtained in Production Example 1 and dibutyl Stirring was started by adding 0.2 g of tin dilaurate and 0.2 g of hydroquinone. The flask was heated until the internal temperature of the flask reached 50 ° C., and 131.2 g of 4,4-methylenedicyclohexyl-diisocyanate (“VESTANAT H12MDI” manufactured by Evonik Degussa Japan Co., Ltd.) was added in portions over about one hour. After reacting at 80 ° C. for 3 hours and confirming the disappearance of the isocyanate group by infrared absorption spectrum, the nonvolatile content was adjusted to 80% by mass using butyl acetate, and the urethane (meth) acrylate resin (1) composition was prepared. Obtained. The urethane (meth) acrylate resin (1) calculated from the raw material charge ratio had an acryloyl group equivalent of 120 g / equivalent, and a weight average molecular weight (Mw) of 4,100.

Example 2 Production of Urethane (Meth) acrylate Resin (2) Composition In a flask equipped with a thermometer, a stirrer, and a condenser, 524 g of the dipentaerythritol polyacrylate (B2) crude product obtained in Production Example 2 and dibutyl Stirring was started by adding 0.2 g of tin dilaurate and 0.2 g of hydroquinone. The flask was heated until the internal temperature of the flask reached 50 ° C., and 90 g of tolylene diisocyanate was added in portions over about one hour. After reacting at 80 ° C. for 3 hours and confirming the disappearance of the isocyanate group in the infrared absorption spectrum, the nonvolatile content was adjusted to 80 mass% using butyl acetate, and the urethane (meth) acrylate resin (2) composition was prepared. Obtained. The urethane (meth) acrylate resin (2) calculated from the raw material charge ratio had an acryloyl group equivalent of 116 g / equivalent, and a weight average molecular weight (Mw) of 4,700.

Example 3 Production of Urethane (Meth) acrylate Resin (3) Composition In a flask equipped with a thermometer, a stirrer, and a condenser, 432 g of the dipentaerythritol polyacrylate (B3) crude product obtained in Production Example 2 and dibutyl Stirring was started by adding 0.2 g of tin dilaurate and 0.2 g of hydroquinone. The flask was heated until the internal temperature of the flask reached 50 ° C., and 131.2 g of 4,4-methylenedicyclohexyl-diisocyanate (“VESTANAT H12MDI” manufactured by Evonik Degussa Japan Co., Ltd.) was added in portions over about one hour. After reacting at 80 ° C. for 3 hours and confirming the disappearance of the isocyanate group by infrared absorption spectrum, the nonvolatile content was adjusted to 80% by mass using butyl acetate, and the urethane (meth) acrylate resin (3) composition was prepared. Obtained. The urethane (meth) acrylate resin (3) calculated from the raw material charge ratio had an acryloyl group equivalent of 130 g / equivalent, and a weight average molecular weight (Mw) of 7,800.

Comparative Production Example 1 Production of Urethane (Meth) acrylate Resin (1 ′) Composition In a flask equipped with a thermometer, stirrer, and condenser, 684 g of the dipentaerythritol polyacrylate (B4) crude product obtained in Production Example 4 Then, 0.2 g of dibutyltin dilaurate and 0.2 g of hydroquinone were added, and stirring was started. The flask was heated until the internal temperature of the flask reached 50 ° C., and 84 g of hexamethylene diisocyanate (“Duranate 50M-HDI” manufactured by Asahi Kasei Chemicals Corporation) was added in portions over about one hour. After reacting at 80 ° C. for 3 hours and confirming the disappearance of the isocyanate group in the infrared absorption spectrum, the nonvolatile content was adjusted to 80% by mass using butyl acetate, and the urethane (meth) acrylate resin (1 ′) composition Got. The urethane (meth) acrylate resin (1 ′) calculated from the raw material charge ratio had an acryloyl group equivalent of 112 g / equivalent and a weight average molecular weight (Mw) of 3,700.

Examples 4 to 6 and Comparative Example 1
125 parts by mass of the urethane (meth) acrylate resin composition obtained in Examples 1 and 2 and Comparative Production Example, 4 parts by mass of photoinitiator (“Irgacure # 184” manufactured by Ciba Specialty Chemicals) and 75 parts by mass of methyl ethyl ketone were mixed. A curable composition was obtained. This was applied on a PET film having a thickness of 100 μm by a bar coater and dried at 80 ° C. for 2 minutes. Subsequently, ultraviolet rays were irradiated at 300 mJ / cm ² with an 80 W high-pressure mercury lamp in a nitrogen atmosphere to obtain a laminated film having a cured coating film having a thickness of 5 μm on the PET film. The laminated film was subjected to various evaluation tests by the following methods. The results are shown in Table 2.

Pencil hardness test About the said laminated | multilayer film, based on JISK5600-5-4, the pencil hardness of the cured coating film surface of a curable composition was measured on 500-g load conditions. The hardness was measured 5 times for each hardness, and the hardness of the cured coating film was determined as the hardness at which the measurement without scratches was 4 times or more.

Scratch resistance test 0.5 W of steel wool (“Bonster # 0000” manufactured by Nippon Steel Wool Co., Ltd.) is wrapped with a disc-shaped indenter having a diameter of 2.4 cm, and a load of 500 g is applied to the indenter to form a laminated film. A wear test in which the surface of the cured coating film was reciprocated 200 times was performed. The haze value of the coating film before and after the abrasion test was measured using an automatic haze computer (“HZ-2” manufactured by Suga Test Instruments Co., Ltd.), and the scratch resistance was evaluated by the difference value (dH). The smaller the difference value, the higher the resistance to scratches.

Flexibility test Using a mandrel tester (TP bending machine "flex tester"), the laminated film is wound around a test bar, and a test is performed to visually check whether or not cracks occur. The minimum diameter was taken as the evaluation result. Test bars having a diameter of 2 mm to 6 mm in 1 mm increments were used.

Curl resistance test A 5 cm square coating film was cut out from the laminated film to obtain a test piece. The test piece was measured for floating from four sides horizontally, and the average value (mm) was evaluated. The smaller the value, the smaller the curl and the better the curl resistance.

Impact resistance test A test was conducted with reference to JIS K5600-5-3. Specifically:
[apparatus]
Weight: A ball bearing steel ball (mass 300.0 ± 0.5 g, diameter 25.40 mm, grade 60) defined in JIS B 1501 “Steel Ball for Five Bearings” is hung with a thread at the tip.
Steel stand: A steel stand having a length of 300 mm, a width of 200 mm, and a thickness of 30 mm installed horizontally on a concrete floor.
[operation]
1. The laminated film was fixed on a steel table with the cured coating film surface facing upward.
2. The weight was hung at a position where the distance from the surface of the laminated film to the lower end of the weight was 50 mm, and after the vibration and rotation were confirmed to be stopped, the weight was dropped on the laminated film.
3. The laminated film after the drop test was left in the room for 1 hour, and then the coating surface was examined for damage.
4). The test was continued with the distance from the laminated film surface to the lower end of the weight 10 mm apart, and the evaluation was performed at the maximum distance at which the cured coating film did not break or peel off.

Claims (9)

The following structural formula (A-1) or (A-2)

(In the formula, l is 0 or an integer of 1 or more, and m is 1 or 2. R ¹ is each independently an alkyl group having 1 to 4 carbon atoms, or a structural moiety represented in parentheses in the formula. And k is 0, 1 or 2, and n is 0 or an integer of 1 to 8.)
A urethane (meth) acrylate resin comprising a polyisocyanate compound (A) represented by any of the above or a modified product thereof and dipentaerythritol (meth) acrylate (B) as essential reaction materials. The polyisocyanate compound (A) is represented by the following structural formulas (A-3) to (A-5).

(In the formula, each R ² is independently an alkyl group having 1 to 4 carbon atoms, k is 0, 1 or 2, and n is 0 or an integer of 1 to 8).
The urethane (meth) acrylate resin according to claim 1, which is a polyisocyanate compound represented by any one of: The urethane (meth) acrylate resin according to claim 1, wherein the dipentaerythritol (meth) acrylate (B) has a hydroxyl value in the range of 50 to 140 mgKOH / g. The urethane (meth) acrylate resin according to claim 1, wherein the dipentaerythritol (meth) acrylate (B) contains dipentaerythritol tetra (meth) acrylate (b1). The urethane (meth) acrylate resin according to claim 3, wherein the content of dipentaerythritol tetra (meth) acrylate (b1) in the dipentaerythritol (meth) acrylate (B) is in the range of 1 to 30%. The dipentaerythritol (meth) acrylate (B) contains dipentaerythritol tetra (meth) acrylate (b1) and dipentaerythritol penta (meth) acrylate (b2), and the ratio of the contents of the two [(b1 ) / (B2)] is in the range of 1/99 to 50/50. The urethane (meth) acrylate resin according to claim 1. A curable composition containing the urethane (meth) acrylate resin according to any one of claims 1 to 6 and a photopolymerization initiator. A cured product of the curable composition according to claim 7. A laminated film having a layer comprising the cured product according to claim 8 and another plastic film layer.